How to Update to PHP 7.4 from PHP 7.x on CentOS 7

READ FIRST -- IMPORTANT !!!Get a complete backup snapshot of your server before you complete these update steps

1. First thing you should do is do any core OS updates and package updates.

   yum update -y

2. Check which version of PHP you are currently running.

   php -v

3. Print a list to see all the PHP packages you have installed. You will need to replace all these packages in PHP 7.4. You should copy this list to a file so you can refer to it if you need to. Make a note of the version of PHP here (7x or 7-x).

   rpm -qa | grep php

   rpm -qa | grep php > php_rpm.txt

4. Remove PHP core and all the installed PHP packages.

   yum remove "php*" -y

5. Install the updated remi repository if it is not already installed.

   yum install -y http://rpms.remirepo.net/enterprise/remi-release-7.rpm

6. Check out a list of all available remi packages (not-required)

   yum repolist remi-safe

7. Disable PHP 7.x and enable PHP 7.4 (Replace x with sub-version of your previously installed version noted above in step 3) and install any extra packages you want / need.

yum --disablerepo=remi-php7x --enablerepo=remi-php74 install php php-pdo php-fpm php-gd php-mbstring php-mysql php-curl php-mcrypt php-json -y

8. Check the updated PHP version.

   php -v

9. Restart Apache to use the newly installed PHP 7.4

   systemctl restart httpd